"Icing" or "frosting" are the terms conventionally applied to a wide variety of spreadable, semisolid confectionery products that are used as toppings to sweeten or decorate baked goods such as cakes, breads, cookies, and the like. Such toppings can be categorized into several basic types, such as royal icings, cream icings, aerated creamy frostings, fluffy frostings, and ready-to-spread frostings.
Icings, e.g., "royal" icings, typically refer to compositions containing primarily sugar and water, and optionally, adjuvants such as emulsifiers to enhance storage stability. As an important characteristic, these compositions generally harden to form firm, nonsticky toppings. Usually, such icings do not contain fat; however, a quick-hardening icing containing 3.3 to 5.9 wt % of a high melting point fat has been disclosed (see U.S. Pat. No. 4,415,601 issued to J. A. Eckel). Also, a heat stabilized icing containing up to about 4% of a high melting point fat, up to about 0.5% of an emulsifier, and up to about 0.1% of a gelling system of xanthan and locust bean gums has been disclosed (see U.S. Pat. No. 4,135,005 issued to H. Cheng). The latter formulation could be referred to as a "cream" or "butter-cream" icing, however, the composition is not aerated.
Cream or butter-cream icing compositions typically refer to compositions containing 40 to 80 wt % sugar, 7 to 21 wt % water, 10 to 20 wt % shortening, and optionally, emulsifiers or other bodying agents. These compositions are usually aerated by the consumer by whipping, upon which the density decreases from about 1.3 g/cc to about 1.1 g/cc. Such icings exhibit a rich and creamy mouth feel due, at least in part, to the high levels of shortening employed. The fats and shortenings commonly used for such icings include butter, margarine, and the partially hydrogenated fats and oils.
"Fluffy frostings" are uncooked, highly aerated, (e.g., &lt;0.8 g/cc) sugary compositions, which are generally shortening-free, or at least very low in fat which typically comes from aerating emulsifiers. Fluffy frostings are typically prepared by the consumer from a dry mix by adding hot water to dissolve the sugar and whipping to form the final fluffy products. The dry mixes generally comprise high levels of sugar and further contain a foaming/aerating agent, such as egg albumin, gelatins, enzymatically degraded soy whipping proteins, or an aerating emulsifier, especially polyglycerol esters of fatty acids. Optionally, the dry mixes can contain very low levels of a wide variety of foam stabilizers, such as sodium alginate, gelatin, or a cellulose derivative, such as carboxymethylcellulose. Fluffy frostings have a unique and desirable mouth feel and eating quality because of their high levels of aeration. However, fluffy frostings are not shelf stable and thus not suitable for use as an RTS frosting.
Ready-to-spread ("RTS") frostings are a popular food product due to the convenience provided by fully prepared products. RTS frostings are thus formulated so as to be usable without the addition of ingredients by the consumer. RTS frostings are stored unopened at room temperature for longer times (a one year shelf life target is typical) or stored after opening at refrigerator temperatures for shorter times. RTS frostings are applied directly from the container to a cake or other baked good without mixing or any other manipulative techniques. RTS frostings form a discrete category of frostings because of their extended shelf lives. Formulation of a low fat, good bodied frosting is relatively simple. However, to formulate a reduced fat, high quality frosting of an RTS type and which maintains its desirable features for a shelf life of over one year is a task so daunting as to heretofore been thought impossible.
The primary ingredient in RTS frostings is sucrose, which contributes not only to sweetness, but also to texture and spreadability. Importantly, RTS frostings additionally comprise elevated fat levels compared to the present products resulting from the high shortening levels and modestly from the low level of emulsifier. Both the fat components, i.e., the shortening and the emulsifier, strongly affect the frosting's texture and spreadability attributes and the ability of the packaged formulation to maintain its qualities for extended shelf lives. RTS frostings typically have a higher fat content, a higher water content, are less aerated, and have a thicker consistency than fluffy frostings. A conventional RTS frosting of the "butter-cream" type can have a composition of about 10 to 20 wt % fat, 7 to 21 wt % water, and 40 to 80 wt % sugar (see, for example, U.S. Pat. No. 3,464,830 issued to I. J. Wahba). RTS frostings usually have about 3.8-4.5 calories per gram, and a density of about 0.95-1.20 g/cc.
Various formulations for ready-to-spread or ready-to-use icings or frostings have been developed in attempts to yield frostings that would match the organoleptic properties of bakery or scratch recipe type cream icings or butter-cream frostings, and that would remain spreadable upon storage in a sealed container for up to about one year. The desired organoleptic and performance properties include a smooth texture, a "short" consistency, spreadability without flowing or running, resistance to syneresis or weeping, and a density of about 0.95-1.20 g/cc. To obtain these desirable properties, conventional RTS frosting formulations often include high levels (i.e., 5 to 30 wt %) of shortening or butter. Other formulations have included additives such as pectin, which acts to prevent syneresis upon storage. Another formulation has used a high fructose corn syrup with a starch to provide the desired body (see U.S. Pat. No. 4,761,292 issued to M. E. Augustine et al.). A composition characterized as a "ready-to-use icing" uses certain selected combinations of triglyceride hardstocks in a shortening component to enhance the aeration, storage stability, and nonfirming characteristics of the product (see, for example, U.S. Pat. Nos. 3,194,666 and 3,253,928, both issued to W. T. Bedenk et al.). Still others have used combinations of glyceridic oils, highly hydrogenated vegetable oils, emulsifiers, gelling agents and/or starches (see, for example, U.S. Pat. No. 3,649,302 issued to E. E. Daggy et al. and U.S. Pat. No. 3,464,830 issued to I. J. Wahba).
While popular, RTS frostings are perceived to be indulgence foods that are high in both fat and calories. Thus, it would be desirable to formulate RTS frosting compositions having the familiar and desirable organoleptic and physical properties of conventional RTS frostings but which also are improved by having reduced levels of fats and calories. Moreover, formulation of dry mixes for reduced fat frostings to be prepared by the consumer is relatively inconvenient. However it is immeasurably more difficult to formulate a ready-to-spread frosting which in addition to being low fat and organoleptically desirable also exhibits extended shelf stability.
Recent attempts to make low fat frostings of the butter-cream type have involved the increased addition of water and the elimination and/or reduction in total fat. Such attempts, however, have typically yielded frostings that are undesirably softer, stickier, and that have a consistency similar to marshmallow cream. Both icings and fluffy frostings can be formulated to be low fat, but such reduced fat compositions generally lack the smooth, creamy texture of high fat butter-cream frostings as well as the ability to retain a spreadable consistency during storage.
In particular, one particular fat-free frosting formulation has the rich mouth feel of a cream frosting and the light texture of a fluffy frosting. However, this formulation contains a comestible base prepared by cooking a blend of citrus juice vesicles, sweetening agents, an ungelatinized starch, and an edible organic acid (see U.S. Pat. No. 4,232,049 issued to J. R. Blake et al.). Reduced fat RTS frostings with the appropriate texture and mouth feel are very difficult to obtain, particularly if less than about 6% fat is desired.
In view of the state of the art, there is a continuing need for RTS frostings that substantially retain the flavor and texture of standard creamy-type, i.e., butter-cream, RTS frostings but which nonetheless have reduced levels of fat and calories. That is, a need exists for a topping that combines the creamy, rich mouth feel of cream icings with a low fat content in a convenient ready-to-spread composition. Moreover, there is a continuing need for such high quality but low fat and calorie frostings which can maintain their desirable properties for the extended shelf lives required for RTS frostings.
Surprisingly, the present invention provides reduced fat and calorie RTS frostings which nonetheless have organoleptic and textural attributes comparable to conventional high fat, high calorie frostings.